1. Field of Invention
The present invention relates to a moving trajectory generation method.
2. Related Art
Recently, due to the rapid development of miniaturization technology, electronic circuits and components have become smaller and lighter while their function, portability and convenience are enhanced. This technology makes the human-computer interaction (HCl) has become one of the indispensable tools in our daily life. In particularly, the hand writing through the HCl is an essential recording or expressing method. Today, many handwriting-based HCl sensing technologies, which mainly include the electromagnetic, electric, supersonic, pressure, and optical sensing technologies, have been disclosed.
However, the electromagnetic HCl sensing technology needs a battery with larger capacity to provide a large power for generating the electromagnetic field so as to detect and position the writing position, which is the pen-point of the writing device. Thus, this type writing device becomes heavier and is inconvenient in carrying. Besides, the electric HCl sensing technology needs to cooperate with a specific electrode paper and use the transmission and receiving electrodes of the electrode paper to detect the moving trajectory of the writing device. Unfortunately, the electrode paper is very expensive, so this electric HCl sensing technology can not be popularized. The ultrasonic HCl sensing technology utilizes the arrival-time difference between the ultrasonic signals and the triangulation location method to calculate the writing trajectory coordinates of the pen-point of the writing device. Although the ultrasonic HCl sensing technology can precisely capture the moving trajectory of the writing device on any 2-dimensional plane, the writing range for receiving the ultrasonic waves with the cooperated receiving device is limited and very inconvenient. The pressure HCl sensing technology has a limited writing range within the area of the pressure sensing electronic board, so its operation is also inconvenient. The optical HCl sensing technology utilizes the optical sensor of the optical mouse to sense the moving trajectory of the writing device on a written plane. The sensing theory is similar to that of the optical mouse, so that it is possible to simply convert the moving trajectory information into the operation signal of the cursor without developing additional application programming interface (API) software.
However, in all of the above sensing technologies, when the writing motion is to write in the air (3-dimensional space) instead of on a 2-dimensional plane, the moving trajectory information can not be easily transformed into the 2-dimensional trajectory signal because the 3-dimensional space does not contain an actual writing plane.
Therefore, it is an important subject of the present invention to provide a moving trajectory generation method that can detect the 3-dimensional moving signal of the writing device and transform it into the correct moving trajectory on a 2-dimensional plane.